Apparatus and method for counteracting the inductance disturbances in telegraph-lines.



. '(1. APPABATUS'AND METBGD POR GOUNTBRAGTINGTHE mnumma f TELBGMPH LINES.

AP-ILIUQIION FILED EAR. 23. 1911.

atexlted Apr, gigi `turbances.

mman siagne .,rarnn'r canina;

CHARLES PRIEST, OF ARLINGTON, JERSEY, ASSIGNOR TO COMMERCIAL CABLE y COMPANY, 0F NEW YORK, N. Y., A CORIORATION 0F NEW YORK.

APPARATUS AND METHOD FOR COUNTERAGTING- THE INDCTANCE IKSTU'IIBANCI?S IN TELEGRAPH-LINES.

0 al A1li/20111, it'mcy/ concern.

Be it known that I, CHARLES PRIEST, a subject of the King-of Great Britain, and resident of Arlington, county of Hudson, State of New Jersey, have invented certain new and useful Improvements in Apparatus and Methods for Counteracting the'Induc-v tance Disturbances in Telegraph-Lines, of which the following is aspeciication.

This invention relates to an apparatus by means of which the instrument used to receive the signals transmitted through submarine cables, under-ground or over-head land lines, is rendered innnune from the disturbances, inductive or otherwise, caused by the proximity of other circuits, such as electric railway circuits, power or other electric circuits, atmospheric or other electrical dis- These disturbances, if not providet. Against, inutilate or destroy the signals transmitted through the said'cables or land lines.

|I`he drawing is a diagrammatic representation of one end of a duplex, submarine, telegraphic cable system, with my apparati connected thereto.

I have shown my invention as applied to a duplex cable system or cii'cuit, but the method is applicable to other' systems and circuits, and I, ot course, desire it'understood that I am not to be limited' to anyspecilic application of the invention. t.

The disturbing elect ofl heavy currents in neighboring power or lightingcircuits upon telegraph or telephone circuits -mayfbe eliminated by two' methods. First by al proc,- ess of 4shielding or protection, whereby the disturbing influencesv are prevented from reaching the signaling circuits; and' second by-a recess or method ot' counterbalancing the e ects of the disturbances. My invention pertains to this latter class. that to accomplish the ldesired result by the vmethod of connterbalancing or compensating for the inductive or other disturbances it was necessary to find a'source ofcurrent, which I define Y as ing line, which Would provide inall cases a disturbance simultaneous with and in all respects equal to, and oppcsitc in direct'on to the disturbance which mutilates thc re erved Specicatidn of Letters Patent.

Application inea March 2a, i911. serial No. 616,372.

" usually termed'the block condensers. pol'esgota battery B are connected tothe a compcnsat y y "strips-.8 land 9 ofthe double key in the usual f Patented apr. 2e, 1era.

i cuit without at the saine time interfering with or otherwise hamper-ing the normal use of `the-circuit for signaling purposes. I found that the best method of controlling and properly introducing thesel counterbaL' ancing disturbances was by means of a condenser and a resistance in series with it through which the source o counterbalancing ldisturbance is connected to the side of the receiving instrument remote lfrom that- .side by which the mutilated signaling currents arrive from the cable or other circuit.

Referring to the parts'illustratedin the drawing, ldesignates the iinder-Water ortion of the main cable and 2 the unlderground land portion thereof, which continuesthe cable connection from the cable hut at the` point where the ,maincable lands to the receiving apparatus at 'thecable oliice.

The land portion of the cable is frequently many miles in length, and is the portion of the circuitin which the disturbing iniuenee of the electric lighting and pnwer circuits is chiefly felt. The artificial line is designated by the numeral 3, the earth plate of said artificial line being designatedby 4. The end of the artificial line is connected to the end of the main cable through-the bridge Wire 5 of the usual VVheatstone bridge', the twonrms 6 and 7 of the bridgebeing connected to the usual double or reversing key K in any suitable manner. The receiving instrumentR is connected to the said bridge wire.,v This instrument may be a siphon recorder or any other suitable foi-mot receiv' -ing'in'struinenh ,v l

'(3v designates a magnetic shunt Which. is

usedltocontrol and regulate .the sizeand'Y vcharacter of the ordinary signals. arriv ingj'from the cable.

In some cases'acon -:l -denser inseries with. the receiving' instru` men'tis used instead ot the shunt. 6, and' sometimes ein addition to the said shunt.`

Condensers C are arranged in the arms 6 and T of the bridge, said condensers being The manner; and key levers 10 and 11 are connected to the line through the 'bridge arms 'tance ,at sea, as indicated in the diagram.

The "connection between key' ll and the sea ,'15 l ratus which prevents ,the signals which enearth consists of a section of under-ground the receiving apparatus, the final effect of' the disturbances arising in it may be neglected as'their `eiect on the receiving'ap- ,paratus is rendered m'Z by precisely the `through the cable.`

same apparatus that is provided to make du-V plex Working possible, that is by the appa'- ter one end of a cable from aiiecting the receiving apparatus situated atthe same end: .Key lever 11 is also connectedto an artificial' line 12, providing an electrical eqmvalent` of-the' under-ground section l1 and the -short submarine section 11".

- The apparatus just described is the-Wellvknown arrangement of a rduplex cable system or Working, for the simultaneous transmission of messages 1n A both directions As hereinbefore stated the 4inductive or other disturbances of the receiving instruother and be so neutralized or.;compensatedl for as to not aii'ect ytheirecferving instrument, or at least affect it. to"l suche slightextent as tonot interfere with the proper reading of the signals. To accomplishl this I connectlto thebridge .Wire at or adjacent its' ,connection to the artificial line a section 15 of insulated under-ground cable corresponding' precisely with the insulated underground portion of the main line cable and subject to the same extraneous electrical ini fluences. This section of cable serves in the compensating disturbances, inductive or otherwise. It will', of course, be understood that this compensating line, or source of inductive disturbances, may be of any form and may be placed in any position, it being desirable that it shall deliver to the receiving instrument on the side remote from the main line connection the same form of disturbances as are delivered to the receiving instrument from the main line cable. I have found it convenient and entirely satisfac-j tory to use as a'compensating line a section of insulated under-ground cable corresponding precisely7 in length, diameterfand character', of insulation with the section 2 of the main line cable. Of course, it is to be understood that any other arrangement may be employed, or any other source of compensating disturbances may be used.` I have found it in sonic forms of apparatus desirable' that theouter end of the compeneating line shall be sealed or insulated in order to `prevent the escape-or dissipation of the induced currents therein, and in order to Iprevent the said compensating line being 1n uenced by local earth currents. Between the compensating line and the receivingr instrument I insert an4 adjustable resistance 16 and an adjustable condenser 17. The disturbances created at any point in the underground cables divide and flow in both di'- rections, that is from the point of origin of the disturbance toward the receiving instrument and,v from the same point toward the main cable. Inas'much, however, as the conlditions at the lfar ends of the under-ground cables 2 and 1'5 are quite dissimilar, it follows .that the amount of disturbance reachmg the ifeccivinginstruments from these two sources is different in the two cases. Thek resist-ance v16 and condenser 17 afford the fnecessary means of restoring the equality .between the tWo sets of distrubance.

In a simplex system and also when using a duplex system for transmission in one direction only, itis only necessary to use the compensating. line with its adjustable condenser and resistance. When, however, it is desired to 4use the system in its duplex capacity provision must be made for balancing the llnes.- ,It is manifest that the insertion of the "compensating line or the surce of lcompensating disturbances with' its condenser and resistance, Vwill so disturb the balance, of the main and artiiiciallines as to entirely 'destroy'the duplex character of the system. To restore. this balance I connect to the. :nain line end ofthey bridge wire a corresponding adjustable resistance 1S and an adjustable condenser 19, the said condenser and -resistance being in series, and

,the ,condenser vbeing connected to the earth plates of the artificial line, as clearly indicatedrin the drawing., By` this `means the balance pf the linesis` completely restored The exact, nature of the sourceof counteractinjdisturbances will depend entirely o n the nature and source of the disturbances to be counterbalanced; If that disturbance arises from a local trolley circuit a local earth connection will serve. If'the disturbances can be traced to any particular source aj direct connection tothatv source will suffice. I have found the arrangement described'herein practically `eliminates the `in- I ductive and other disturbances in the receiving instrument, or at least reduces ,them to such an `extent that they do not interfere 'with the proper reading ofthe signals.

aling system. -,comprisaid line, a source ofextraneous inductive disturbances of; like and di'rectlyand independently conn edto the receiving instrument on the'opposite Y side thereof from` the main line. c'o'nnec. -tion, the two sources of inductive.d'isturb' I' ances being independent of eachother and .unafected by each other outside 'of the ceiving instrument, whereby the inductive disturbances picked u'p by the mainline and L the si'milar disturbances -from the .compensating source willfpass to the receiving instrument. un'aected and independently of 2. Anv electricsignaliiig -system comprisingamainline subjectto extraneous e1ectrical inductive disturbances,` a receiving in.-

strument connected to said line, an insulated wire serving as a compensating line and c'orresponding to a portion only o themain lineand subject to extraneous inducti edisturbances of like character to-those a `'ecti'ng the main line, the compensating line being independently connected to the receiving inf.

line, said wire being independent of the main strument on the opposite side thereof from the main line connection, the inductive disturbances picked up by the inain line'beingl .`unat'fected bythe corresponding inductivedisturbances picked up by `the compensatingline,"said disturbances `flowing to the receiving instrument in opposite directionsl and balancing oi' neutralizing each other in. the. receiving instrument. A w

3; A iduplexz telegraph system comprising a inain .line subject to extraneous electrical.' disturbances, an artificial line, a.- rece1vingA instrument connected to both of said lines,

.anda compensating line connected to there;

ceiving instrument on the opposite side thereof; from the mainline connection and subject'to extraneous electrical distiirbances similar to tliose affecting the main line.

4. A Aduplex ,telegraph system comprising main and artificial lines, a receiving instrument connected to l'iotli of. said lines, a compensating line connected to the .receivin0 instrument on the opposite side thereof, om the main line connection,- a resistance and a condenser interposed between the' compensating line and the i'ccei'vmg instrument, a

resistance and aV condenser 'connected 'to 'the receiving instrument at'the main line connection thereof and means connecting this latter condenser to the earth plate of the' artificial line.

'receivingjiiistrument on th'same ,i Y Having thusfu'lly described'my'invention, 5.- A -cble telegraph 4systemcomprising .what I claim as new and desire to Asecure by Letters Patent, isz* 1l-An4 electric si ing a main line sub]ect to extraneous electri-` cal'indu'ctive disturb ces', a receiving instrument connected t n n underwater portion and. 'an .underground portion, a receiving-instiiiinient. connected totlie free end of the 'undef-ground oi'tion, an insulated.compensating cable 70 corresponding to' the [under-'ground ortion of the mainl lineic'able andtaijrange to be subject to the sameextraneous electrical influences, the outer orfree encl"of said compensating cable'beingsealed or insulated, the 'inner end off said `cable being connectedto the. receiving instrument on lthe opposite .side thereof from Itlie main line conductor.

6. A- duplex cable system comprising a ma-in under-water secti0n,an under-ground or land section, an artificial line,afrece iving instrument connected to both of s'aid lines, a compensating -cable-corresponding iii length to the under-ground port-ion of the main line and arranged to 'be subject-to the 85- same extraneous electrical iniiuences and-.1n lcoiinecte'dlo the artificial line end-lof thefre- 'ccivingl instrument, yav condenserandaj're. sistanc'e interposed between said compensati ing cable and the receiving-instrumentfthefinsulated, a resistanceanda'conenser coii'yv` nected tothe receiving. instruii'ieiitfat the' jmain line end thereof, .said condenser' bein" also'connectejd'to theeartli plate o the arti- {icial line. 7. A- duplex telegraph' system comprisin al main line .subject-to extraneous electrica disturbances, Aan artificialline,l a' receiving -instrument connected to both 'of v'said lines, vand a source. 'of compensating electrical dis turbancesconnectedfto the receivin yin stri'inient 'ontheopposite side thereof'ig-rom tli'e' main line connection and similar to the'extraneous electi'icalisturbances' atectingthe -rnain line', -wliereb `the extraneous electrical disturbances-in' t e main line will be' balanced bysimilar disturbancesiconnected toV -the opposi'tevside ofthe receiving instrument.

-8.. A duplex telegraph systemcomprising a mainline, an artificial line, a receiving im. strument connected to both, of said lines, anda.- source 1f-compensating electrical listurbf` ances connected ltothe, .recevinginstrume on the opposite sidetheteof frqm'thejil.' line connection, and means coi'ine'ctedv t 'i th ico of 'with tlicni'a'in line connection:toY the' duplex' working balaneein thev 9. A duplex telegraph system com i a main line subject toextrnefs'iiiiic disturbances, an artificial line,'v;areceiv instrument connected to botli'gol salid Ali and a source of compensatinggextran'eons ductive disturbances connected to thereceiu f inginstrument -o'n the opposite sidezthereoi from the main line connection and balancing y the extraneous nductvedisturbaiices intliefJ inain line. i

outer .end'of'the said-cable lieinv s ealedforv e.

1Q.. A duplex telegraphsystemccoinprisigf; Y

' a main linesu'bject to inductivedisturba`nces, v-an artificial line', a receiving instrument c'on' nect'e'd to both of vsaid lines and a; source ofcornpensatinginductive .disturbances conn fnected to the receiving instrument.4 on the- -`f opposite side thereof from. thejmain line conh ne'tion; and balancing the inductive disturb' 4arnice'sin the mainline, andlmeans .conected' :tdthe l"eceiving instrument on the sameside' 10 'thereo with the.-main1i ne -l connectionto maintain the duplex wv'orking balance.'

raneous ingiuntivoV disturbances in telegraph l2.- A cable telegraph .system 'comprising amainline Wire, a receiving instrument conf 'f'necte'dto thel main line, an insulated com- -2'5 -'pensating'xvire arranged to b e subject to -the l'Sam'e'extraneous electrical influences affectl the mainxline and'conneetedto the rel c'elving. instruxr'i'entgon-gthe opposite side thereof. from the main line connection, a con- 39 denser and -a resistance 'interposed .between `said ,compensating.lineand the'receivi'ng in` fgstrumentjtheonter end of said compensating linebeing sealed or insulated, for4v thepurpose 'set forth. o

.35.- 13.` 'A1 duplex ca'ble system-'comprising -strument=onnec`ted to both of said lines, a

A iompe'nsating line arranged torbe subject tothe'same egtraneous electricalfiniuences afinainl-ine and -connected to the .1a. '1ine'.ed.of the receiving instru--A merit, Iidenser and a resistance inter- "p'os'ed" tweensaidlcompensating line and vther ivin'gjn'strument, the. outer end.of

4hf1said: cmpensatingtln being sealed or inf 'sulatedj'andf a', resistance and a condenser connected. tothe receiving ,instrument at the signin-line sidefthereof; said condenser 'and' .resist-ance being alfsoconnected to.- the 'earthv .Y

f v Witnesses:

Sofplate'gofjthe artiiicial line.

line nini-ef,4 a rsreiving instrument connected,-

' i.: lines which-consists in' 'connecting`to the re-y ill'vbe'balnnced in the receivinginstrument.-

A legFaph system eomprisingiamain- :to the main line and 'provided withan earth. connection on the opposite side thereof from -themain line.connection, 'a. compensating- A55 wire or.; conductor, said compensating wire being arranged to besubjected to the same 'extraneous electrical iniiuences l affecting the main line wire-and 'connected to the receiving instrument on theopposite side thereof o0 to the main line. conductor and extending for .onlya portion of the lengthofthe main linez whereby the impulses of eurrent'picked 'up by 'saidcomp'ensating line flow to the receive. i

-ing instrument and neutralize the' disturb- 65 ing imulses picked up by the main linc. l5. telegraph .system comprising' a main line wire, a receiving instrument connectedto the main line and provided lwith an earthconnection on the opposite side thereof from 7`0 vthe mainline connection,` a compensating wire or connector" arranged 'to be subjecte to the saine extraneous electrical influences affecting the main line wire `and'co nnected to the receiving instrument onrthe opposite 76 .side thereof from the main line conductor, f

vsaid compensatingwire being insulated at lits outer end, a resistance -and a condenser interposed 1nV said 'compensating llnefnear its connectiofn vvitli the receiving instrument- 80;

' 16. An electrlc` signaling system comprising a main/line subject jtdextraneous electricahindnctive, disturbances, a receiving .in- I strunie'nt connected 'to said 'main line,",-"an insulated vv'source Vof` compensating extrane- -85 vofus'electriol inductiifedisturbances'free of p. "the main line normal ciirrents and connected to the receiving'instrulnent ion the oppositel side t\'ereof` dtrnn the main' .1ine,' a." c0n' densernd- 1f-resistance interposed between 90 the source fof-compensating inductive disf" turbances vand 'the .receivin' instr uxrie nt,v and an 'artificial` cableconnecte to the'same' side' ofthe receiving instrument'asthe insulated 'source of compensating'jmductive '.disturb- 95.

ances said artificial cablefhaving the usual earth plate. l' .A l I I .Intestimony whereof I hereunto alix my signature in thep'resenceof tyyovvitnesses.

.-CHARLEs'rRiEsT.. 

